Petrillo in U.S. Pat. No. 4,168,267 discloses that phosphinylalkanoyl substituted prolines are useful as hypotensive agents due to their angiotensin converting enzyme inhibition activity.
Petrillo in U.S. patent application Ser. No. 212,911 filed Dec. 4, 1980, now U.S. Pat. No. 4,337,201, discloses that various acyloxyalkanoyl esters of phosphinylalkanoyl proline and substituted prolines are useful hypotensive agents due to their angiotensin converting enzyme inhibition activity.
Rovnyak in U.S. Pat. Nos. 4,211,786; 4,254,267; and 4,266,065 disclose that mercaptoalkanoyl derivatives of 4,5-dihydropyrazole-5-carboxylic acid, wherein the dihydropyrazole ring can also be substituted in the 3-position by an aryl, heteroaryl, or alkyl group, are also useful as hypotensive agents due to their angiotensin converting enzyme inhibition activity.
Ondetti et al. in U.S. Pat. No. 4,105,776 disclose the mercaptoalkanoyl derivatives of proline are useful hypotensive agents due to their angiotensin converting enzyme inhibition activity.